Cells - Structure and Function

What is life?

What is life? Life is everywhere, but it resists a simple one-sentence definition. Some of the properties of life are given below:

Important Events in the Discovery of Cells

The Cell Theory of Biology

Properties of Cells

Cells are complex and highly organized

Cells contain a genetic blueprint and machinery to use it

Cells arise from the division of other cells

Cells aquire and utilize energy

Types of Cells





Features of Prokaryotic Cells

  • Capsule - outer sticky protective layer
  • Cell Wall - rigid structure which helps the bacterium maintain its shape
    • this is in NO way the same as the cell wall of a plant cell
  • Plasma membrane - separates the cell from the environment
  • Mesosome - infolding of plasma membrane to aid in compartmentalization
  • Nucleoid - region where nakedDNA is found
  • Cytoplasm
    • semi-fluid cell interior
    • no membrane-bound organelles
    • location for metabolic enzymes
    • location of ribosomes for protein synthesis


Properties of Eukaryotic Cells


Images of Vesicle Transport Between Endomembrane Organelles  


Endosymbiotic Origin of Chloroplasts and Mitochondria